Download Elementary Institute 2010 Bone and Brawn

NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
Bone and Brawn
Bone Basics
Made of: Compact (aka dense) bone, and spongy bone. Most bones contain both types. Compact
bone is dense, hard, and forms the protective exterior portion of all bones. Spongy bone is
inside the compact bone and is very porous (full of tiny holes).
How many? 300+ at birth, 206 as adults
Why does it change? As you grow, some of your bones fuse together
Skeleton: All your bones working together
Structure: Gives you your shape! Otherwise you would be a blob.
Support: Holds up the weight of your body and all its organs
Protection: Protects important organs like your brain, heart, and lungs
Joints: Allow you to move in some directions without moving in others (you wouldn’t want to bend
your knee backwards!) Different joint types allow for different types of movement.
Fun Trivia:
Most broken bones aren’t actually broken, they are fractured. It is basically a crack in the bone.
The femur is the largest bone in the body
More than half of the bones in your body are found in your hands and feet
Muscle Basics
How many? 640ish in adults, varies by source.
What do they do? Produce force and cause motion
Ligaments: Attach muscle to muscle
Tendons: Attach muscle to bone
Muscle reactions
Voluntary: You can control them by thinking about them, like lifting your arms or bending your knee
Involuntary: Your body makes them work without you realizing it, like breathing or your heart
beating.
Both: Some muscles can be both voluntary and involuntary. For example, you can make your eyes
blink or hold them closed, but if you don’t think about it your eyes will blink on their own
automatically
Types of Muscle:
Skeletal: "voluntary muscle" is connected by tendons to bone and is used to control movement and
in maintaining posture. Is striated- muscle fibers bundle together. Approx. 40% of body
mass in adults is skeletal muscle.
Cardiac: "involuntary muscle" similar in structure to skeletal muscle, found only in the heart. Is
striated- muscle fibers bundle together
Smooth: "involuntary muscle" is found within the walls of organs like the stomach, intestines, and
throat. Unlike skeletal muscle, smooth muscle is not under conscious control.
Fun Trivia:
Strongest force exerted by a muscle is the jaw muscle (biting force), of 975 lbs for 2 seconds
Largest muscle in your body is the Back muscle (Latissimus Dorsi)
By the time you turn 70, your heart will have beat some two-and-a-half billion times
It takes 17 muscles to smile --- 43 to frown.
NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
Bones You Should Know
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Ankle
Collar Bone
Femur
Fibula
Fingers
Heel
Hips
Humerus
Jaw
Knee Cap
Radius
Ribs
Skull
Spine/Vertebrae
Sternum
Tailbone
Tibia
Toes
Ulna
Wrist
Types of Joints:
Ball and Socket (Shoulder, Hip)
Hinged (Elbow, Knee)
Gliding
Saddle
Ellipsoid
Muscles You Should Know
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Abdominals
Back Muscle
Biceps
Calves
Chest Muscle
Diaphragm
Glutes
Hamstrings
Heart
Quadriceps
Triceps
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Achilles Tendon
Types of Muscle:
Smooth
Cardiac
Skeletal
Ligament vs Tendon
NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
**Heart and diaphragm are not shown
NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
NC Science Olympiad
Elementary Institute 2010
Bone and Brawn
Gliding and Saddle
Hinge - A hinge joint allows extension and retraction of an appendage.
Ball and Socket - A ball and socket joint allows for radial movement in almost any direction. They are found
in the hips and shoulders.
Saddle - A saddle joint allows movement back and forth and up and down, but does not allow for rotation
like a ball and socket joint. Your thumb is a saddle joint where it joins your palm.
Pivot - Pivot joints allow rotation around an axis. The neck and forearms have pivot joints.
Gliding - In a gliding or plane joint bones slide past each other, like between your wrist and your palm.
All images in this document are from Google images